Best for her to stay off it as much as possible til it heals.
My experience with plantar fasciitis-(yes I read the article and am not confusing the two problems) is that limping around with one sore foot leads to knee injury, then the other foot gets it, ankles and hips get stressed, etc. leading to a world of pain. Finally I stayed off the feet and got better quickly. Resting is what the article recommends and I'd stick with that. Orthotics help some people but I found they often created other problems. If she does get a heel cup, make sure she gets one for each foot and does not favor one foot above the other. Good luck, it is no fun having a sore foot.
"...forever wild..."
Baxter State Park
55 years old, 5'4"
1/1/11 weight: 172 and grumpy
Lost 7 lbs on calories in, calories out
Went paleo/primal 1/1/12
Current weight: 144 and happy
Goal weight is 130 more or less